# Copyright (C) 2017 Beijing Didi Infinity Technology and Development Co.,Ltd.
# All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ==============================================================================
""" base interface of Frontend """

import abc
import tensorflow as tf


class ABCFrontend(metaclass=abc.ABCMeta):
    """ abstract of Frontend """

    def __init__(self, config):
        raise NotImplementedError()

    @abc.abstractmethod
    def call(self, *args):
        """ implementation func """
        raise NotImplementedError()


class BaseFrontend(ABCFrontend):
    """ wrapper of abstrcat Frontend"""

    def __init__(self, config: dict):
        self._config = config

    @property
    def config(self):
        """ config property """
        return self._config

    @classmethod
    def params(cls, config=None):
        """ set params """
        raise NotImplementedError()

    def __call__(self, *args):
        """ call """
        return self.call(*args)

    def dim(self):
        return 1

    def num_channels(self):
        return 1
